If you wish to go out onto the streets to follow the parade, make sure you get out of the shrine before 12 as they block off the exit right before the mikoshi leave and it becomes so cramped in there that you literally can’t move. Otherwise, you can follow the mikoshi from a distance after they leave and the exit clears. Anyone can participate in the parade, and the shrine actually loans out kimonos to anyone wanting to don one and join in.